We've got plenty of containers in the module that allow you to look at but not take their contents. It'd be cool if furniture owners could toggle a similar feature.
The major issue with player run properties being used as things like Galleries or Museums is anyone can just take things out of the displays if the owner isn't present, meaning you can't really leave it publicly accessible.
Having this toggle removes that risk, and means stealing from player properties requires a DM as it should probably anyway.
Also, if it could be separately toggled for both putting items in and taking items out, it allows for delivery and dropboxes only the owner can take from without a DM.
This would be really good.